1. Field of the Invention
The present invention relates to a ceiling air passage system for vehicle air-conditioning. The ceiling air passage system includes three-dimension passage structure, and innumerable ceiling air outlets from which conditioned air is blown downward in a passenger compartment.
2. Description of Related Art
For example, in JP-U-62-3310, a ceiling air passage system for a vehicle air conditioner includes a large number of ceiling air outlets from which conditioned air is blown downward in a passenger compartment. Specifically, an upper plate is disposed at a lower side of a vehicle roof, and a lower plate is disposed at a lower side of the upper plate while a predetermined clearance is provided therebetween. A bag-shaped air passage is provided between the upper and lower plates, and the ceiling air outlets are provided in an entire surface of the lower plate or in a part surface of the lower plate. In this way, conditioned air (cool air) from an air conditioning unit is blown into the bag-shaped air passage through an air duct. Then, the conditioned air in the bag-shaped air passage is blown downward in the passenger compartment from the ceiling air outlets provided in the lower plate.
However, in this ceiling air passage system, the bag-shaped air passage is provided to simply extend in the entire back surface (lower surface) of the vehicle roof. Therefore, when the conditioned air is blown into the bag-shaped air passage from the air duct, the conditioned air flowing in the bag-shaped air passage deflects in a direction due to the dynamic pressure of the blown air. As a result, the conditioned air cannot be blown uniformly from an entire area of the bag-shaped air passage.